1. Field of the Invention
The present invention relates to color filter substrates and display devices. More specifically, the present invention relates to a color filter substrate preferably used in multi-primary color display devices which display characters, images, moving images, and the like; and a display device such as a liquid crystal display device, and such a color filter substrate and a display device are used in a cellular telephone, for example.
2. Description of the Related Art
A color filter substrate is one member equipped with a display device to provide color display, and generally, on such a color filter substrate, a plurality of colored layers is regularly arranged in every pixel. As a combination of colors of such colored layers constituting the pixel, three primary colors of red (R), green (G), and blue (B) are used. In such a combination, however, a range of color which can be observed by human eyes can be only partly displayed, and therefore the color reproduction range is limited. Therefore, a configuration in which colored layers of four or more primary colors (hereinafter, also referred to as “multi-primary colors”) are arranged in every pixel in view of expansion of the color reproduction range now has been proposed.
A color display device configuration in which sub-pixels of R, G, B, and yellow (Y) are arrayed in a matrix pattern, as shown in FIG. 5, was disclosed as such a multi-primary color filter substrate, for example (for example, refer to Patent Documents 1 and 2). However, according to this configuration, the sub-pixels are arrayed in order of hue (in order of R, Y, G, B) in the clockwise or counterclockwise direction, and R and G which are opponent colors, and Y and B which are opponent colors, are diagonally arranged with respect to each other, respectively. Therefore, the color lights are insufficiently mixed. Therefore, if a straight line is displayed with a mixed color, color separation of the straight line is observed. Particularly if a straight white line is displayed with a mixed color of RGBY on a black background in the row or column direction, the color separation is more clearly observed. In this point, such a configuration has room for improvement.
A configuration in which the above-mentioned sub-pixels of four colors are arrayed in a stripe pattern, as shown in FIG. 17, was disclosed (for example, refer to Patent Document 1: WO 03/088203 and Patent Document 2: Japanese Kokai Publication No. 2001-209047).
Also in this configuration, however, the sub-pixels are arrayed in order of hue in the array direction (row direction), and therefore R and G which are opponent colors, and B and Y which are opponent colors are arranged with another color therebetween and the color lights are insufficiently mixed. Accordingly, if a straight white line is displayed with a mixed color of RGBY on a black background in the direction perpendicular to the array direction of the sub-pixels, color separation of the straight line is observed. In this point, such a configuration has room for improvement.
A pixel configuration in which a color unit of R, G, B, and white (W) is arrayed in a matrix pattern in order of R, G, W, B in the clockwise direction, as shown in FIG. 18, was disclosed (for example, refer to Patent Document 3: U.S. Pat. No. 5,642,176). However, such a configuration has room for improvement in that its color reproduction range is smaller than that in a pixel configuration constituted by a normal RGB color unit, because W is not a chromatic color.